Expansible metallic core for curing pneumatic tires



Jan., 9,' 1923. 1,441,649.

E. WRIGHT.

EXPANSIBLE METALLIC CORE FOR CURING PNEUMATC TIRES F|LEnNov.6.1s2o.

" VEN 70H.

D VVR/@Hr pands the same within the carcass.

Patented dan. 9, M33.

tl lil l lll httlgttt lil on narrow, onro.

Application :tiled November 6, i920. Seriallto. 422,161.

fo all 'whom t may concern.'

Be it known that l, EDWARD lll/nien'r, citizen of the United States, residing at Dayton, in the county or" lvlontgon'iery and State ot Qhio, have invented certain new and useful flniprovements in EXpansible Metallic Cores for Curing Pneumatic Tires, o' which the following is a specilication7 reference being hadk therein to the accompanying 1 drawing.

This invention relates to an expansible metallic core for curing or vulcanizing pneun matic tires and the like.

In the manufacture of pneumatic tires it has been common practice to cure the same on an air bag77 which consists ot' a flexible annular tube adapted to be inserted in the carcass of the tire `and to receive fluid under pressure, such as steam, which en* These bags, or flexible cores, are open to several objections among which arel the expense involved in constructing the same and the very short lite oli' the bags. llt has been 5 proposed to provide an expansible metal bag having a longitudinally extending reentrant portion which will permit the metal bag to expand. ln the case of a metal bag, however, it is necessary that the core be made in a plurality of segmental sect-ions to permit the saine to be collapsed tor removal trom the tire. Each section being a coinplete unit in itself must have its ends closed and the closures, or end walls, interfere with or entirely prevent the expansion ot the core sections at their ends. Consequently, with these cores each section will have a relatively large expansion mi'dwaybetween its ends with very little ory no expansion at the eXtreme ends thereof, which renders the core objectionable in practice.

The object of the present invention is to provide a metallic core, each section of which will have substantially uniform expansion throughoutits length. f

A further object of the invention is to provide an expansible core of such a character that the tire may be built up on the core and cured thereon.

A further obj ect of the invention is to provide a core of this character which will be simple in its construction, inexpensive to manufacture, and which will have a long life.

@ther objects of the invention will appear as the device is described in detail.

ln the accornpanyino' drawings Fig. l is a side elevation, partly in section, of a p0rtion ot an expansible metallic core embodying my invention; vFig. 2 is a sectional view taken transversely of such a core showing the within the tire and the tire within the mold; Fig. is a sectional View showing the manner of bridging the joints between adjacent core sections; F ig. l is a sectional detail view showing the stops to limit the expansion ci. the core; and llig. 5 is a fractional detail view ot a portion'oi a core section showing a modified arrangement of the inlet tube.

ln these drawings l have illustrated one embodiment of my invention and have shown the core as comprising a plurality of segmental sections, one full section, l, and parts oi" two motions, ,Q and 3, being shown in Fig. l. The several sections are adapted to be arranged end to end to form a complete annular core. ln order that the core may be collapsed, one section is formed of a wedge shape so that it can be withdrawn inwardly trom the tire, and in Fig. l l have shown the section 3 and the adjacent end of the section l as having` their ends oblique, or non-radial, and it will be understood that the opposite end of Fig. is inclined in the `opposite direction from that shown in Fig. l so that the section can be withdrawn lafter the manner of a wedge.

lach segmental section, or unit7 of the core comprisesa tubular structure, or body portion, having hollow walls which Yforni fluid tight chambers. The side walls 4 of the structure are curved to conform them substantially to the contour ofthe interior of the tire to be cured and the closed outer edges of the side walls are arranged adjacent one -to the other, preferably along the center line of the tread of the tire.` rl`he side walls are preferably connected one to the other at their inner ends and, as shown in llig. 2, the side walls are connected by a transverse wall 5, the ends of which are in open conimunication with the side walls, thus uniting the interiors of all the walls to form a single Huid tight chamber. F luid under pressure, such as steam, be admitted to this charnber in any suitable `manner and, as `here shown, ll have provided the same with an inlet tube, or valved nipple, 6 of ordinary construction. The hollow walls of the several andconnected one to the other by a union 17 to Vpermit them to be readily disconnected. 1n this manner the steam may be admitted tot. one section and will `circulate from section to section about the entire core. A suitable outlet is provided for the steam and in the present drawings this is shown as a valve controlled outlet pipe 17a. When Huid under pressure is introduced into the hollow w'allsof the coreit will tendto move the closed end portions of the side walls apart and to thus expand the core. nas much as the space between the side walls of the core does not contain a fluid it need not be closed vand l prefer to leave the ends of each section open. Consequently, there are no endwalls` or other end structure, to interfere with the free expansion of the end portions of the sections. The closed ends of the walls will offer some slight resistance to the expansion of theend portions vof the wall but this resistance is minimized by flaring the` ends of the walls outwardly, as shown in Figs. l and 3. Consequently, each core section will have a substantially uniform. expansion throughout its length. 1f, under certain conditions, it should be found that the end portions of the core do not expand with the same freedom as the intermediateportion thereof the expansion of the ends may be increased by inserting therein springs 7 which will act on the end portions of the core to expand the same but which will not be of sufficient strength to expand the core in the absence of luid pressure. When the core is subjected to the action of fluid under pressure the pressure of the l springson the end portions of the core sections will serve to increase the expansion of the end portions thereof sufficiently to make it uniform with the expansion of the intermediate portion.

When the core is subjected to the action of fluid under pressure it will be apparent that the outer edge portions of the side walls will expand to a greater extent than will the inner portions thereof and 1 prefer, there fore, to provide stops which willcheck the expansion of the edge portions of the side walls when these have expanded to a predetermined extent. Vhen the expansion oi the outer portions of the side walls has been interrupted the action of the Huid will tend to further expand the inner portions thereof, thus causing the whole of the core to be expanded to the desired extent. The stops may be of any suitable character and, as here shown, they comprise arms 8 which are rigidly secured at their outer ends to the respective side walls 4.-, near the outer edges thereof, and the inner ends of which overlap and are connectedv one to the other by a pin and slot connection 9, asshown in Fig. 2,. the length of the slot being equal to the amount of expansion it is desired to impart to this portion ofthe core. lThe space betweenthe closed ledgesof the side walls Ymay be bridged by a strip of metal, or the like, 10which is rigidly, securedl along one edge, preferably lby brazing, to one of the side walls, andthe other edge of which overlaps the other sidewall and bearstightly yagainsi: the same. The-strip 10 is fof thin material and the lateral portions thereof are tapered to feather edges so that it forms buta lsmall projection on the surface ofthe core.l The joints between the endsof adjacent sec-tions are bridged in much the saine manner but in this instance the bridging strip is divided horizontally into two parts, one of the parts, as shown at l1, being rigidly secured to the end of one section and overlapping the adjacent section, while the 'edge of the other portion, or strip, 12y is rigdly secured to the lastmentioned section and overlaps the first mentioned section. In lthe case of the wedge shaped sections 3 it is, of course, lnecessary that the innery guard stripf12 should` be rigidly secured to y,and vcarried by the wedge shaped section so that it can move inwardly therewith.

The several sections of the core 'may Ibe connected one tothe other and held in their proper relative positions in any suitable manner, but in the device here shown l1 have provided a two part clamping rin-g 13 having an exterior diameter which will cause it to iit snugly againstv the inner walls ofthe core sections when these are in their properly assembled positions. The clamping ring may be attached to the cores in any suitable manner, by causing' the saine to `engage suitable projections from the coreand, inthe present instance, I1 have vprovided the two parts of the clamping ringwith recesses 14 adapted to receivethe tubes 46` andvl ofthe several sections, andV toclamp these tubes between the two kparts of the ring, thus Yattaching the ring firmly tothe several sections of the core and `*retaining theseA sections rigidly in their properly assembled positions. j j *l Where such a core is to'be used forrepiair purposes a single section, -or'unit,-mayfbe employed. This vunit need not Idiier in any yway from'the units of the annular 'core but 1 prefer that theinleft` tjube,or nipple,ibe arranged within the tubularstructure instead of exterior thereof, as shown at 15 in Fig. 5. In this way the nipple is arranged in a Cfr Leeneae position where it is not liable to injury due to the rough handling of the core and in which it will not interfere with tht use of the vulcanizing molds, which usually extend entirely about the tire.

The operation of the device will be readily understood from the foregoing description of the several parts thereof, and it will be apparent'tha't l have provided a metallic core, each section of which will have substantially uniform expansion throughout the length thereof and which will expand not only at the joints between the side walls but throughout the area of the side walls. Further, it will be apparent that the device very simple in its construction and that it will have a relatively long life inasmuch as the material and construction are such that it will not rapidly deteriorate from use.

.lt will be understood that the core is formed of thin sheet metal and that in the present drawings the thickness of this metal has been exaggerated in order to facilitate the illustration of the device.

lFVhile l have shown and described one embodiment of my invention l wish it to be understood that l do not desire to be limited to the details thereof as various modifications may4 occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by `Letters Patent, is:

l. ln a vulcanizing core, a structure having a hollow curved wall forming a fluid tight chamber, andmeans to introduce fluid under pressure into said chamber. j v

2. 1n a vulcanizing core, a structure having a hollow curved wall forming a fluid tight chamber', the ends of said hollow wall being free to move, and means to introduce fluid under pressure into said chamber.

3. ln a 4vulcanizing core, a structure having oppositely curved hollow walls arranged with their adjacent edges parallel, and means to introduce fluid under pressure into said hollow walls.

fl. n a device of the character described, a tubular structure having hollow walls shaped to conform to the interior of a tire, said walls having their longitudinal closed edges arranged adjacent one to the other but unconnected to permit of the relative movement thereof, and means to introduce fluid under pressure into said hollow walls.

ln a device of the character described, a tubular structure open at its ends and having' hollow walls shaped to conform to the interior of a tire, the longitudinal closed edges of said walls being arranged adjacent one to the other and being capable of relative movement, and means to introduce duid under pressure into said hollow walls.

6. ln a device of the character described, a tubular structure open at its ends and having curved hollow walls forming liuid tight chambers, the adjacent edges of said walls being movable relatively one to the other, and means to introduce fluid under pressure into said walls.

'7. In a device of the character described, a tubular structure open at its ends and having curved hollow walls forming fluid tight chambers, the adjacent edges of said walls being movable relatively one to the other, means to introduce fluid under pressure into said walls, and means to limit the rela-tive movement of said walls.

8. ln a device of the character described, a tubular structure open at its ends and having curved hollow walls forming fluid tight chambers, the adjacent edges of said walls beingmovable relatively one to the other, means to introduce fluid under pressure into said walls, and stops carried by said walls near the adjacent edges thereof to limit the relative movement of said walls.

9. ln a device of the character described, a plurality of segmental sections adapted to be arranged end to end to form an annulus, each section comprising a tubular structure open at its ends and having curved hollow walls forming fluid tight chambers, the adjacent edges of said walls being movable relatively one to the other, lan inlet tube ei;- tending inwardly from each of said sections and communicating with the respective hollow walls, and clamping rings embracing said inlet tubes and fitting against the inner edges of the several sections of said device.

l0. ln a device of the character described, a tubular structure open at its ends and having curved hollow walls forming fluid tight chambers, the adjacent edges of said walls being movable relatively one to the other, a guard strip carried by one of said walls near the edge thereof and over apping the adjacent edge of the other wall, land means for introducing fluid under pressure .into said walls.

ll. ln a device of the character described, a plurality of sections arranged end to end and each comprising a tubular structure open at its ends and having curved hollow walls forming fluid tight chambers, the adjacent edges of said walls being movable relatively one to the other, means to introduce fluid under pressure into said walls, a guard strip carried by the outer portion of the end of' one section and adapted to overlap the end of the adjacent section, and a second guard strip carried by the inner portion of the end of said second section and adapted to overlap the inner portion of the first mentioned section.

l2. 1n a device of the character described, a tubular structure open at" its ends and having curved hollow walls forming fluid tight chambers, the adjacent edges of said walls being movable relatively one to the ture and capable ol movement relatively one to the other throughout the length of said structure, and means to introduce fluid under pressure into said hollow walls,

14. ln a. vulcanizing core, an arcuate tubular structure having hollow walls shaped to coniorm to the interior or a tire.)V said hollow `walls having their longitudinal closed edges. arranged adjacent one to the other along the outer circumference o1 said structure and each of said wlls having its inner and outer members connected directly one to the other at their respective ends7 whereby said walls are capable or relative movement throughout the length of said structure, and means to introduce fluid under pressure into said hollow walls.

15. An expansible core for tires, an arcuate tubular body having hollow walls, said tubular hollow walled body being longitudinally split upon the external circumferential side whereby the respective sides oli the member are separable under the influence olf internal pressure, and means :tor applying internal pressure to expand the core.

16. An expansible core for tires comprising a substantially tubular arcuate shell longitudinally slotted upon its outer face, the separated portions ot' the shell being laterally dellectable under the influence of internal pressure,.and means 'for applying internal pressure thereto.

17. An expansible core for tires comprising an arcuate member longitudinally bifurcated on its convex tace, the bifurcated portions being inturned and terminating in proximity one to the other, and pressure apneaneee f plying means tor detlecting said biiurcated portions laterally.

18. ein expansible. core lor tires comprisan arcuate tubular member conforming substantially to the interior oli a tire,v said tubular member in that portion contiguous to the tread portion of the tire to Yform relatively kadjustable wingsj and means 'for applying pressure for distending said wings.

19. r-lrn expansible core for tires comprising an arcuate member having two relatively movable inturned wing portions approximately nieeting at a point contiguous to the tread portion of the tire, and means tor applying pressure to said member 'for flexing 'the -.viini; portions thereo outwardly.

20. An expansible lcore for tires comprising an arcuate member having two relatively movable inturned wing portions approximately meeting at a point contiguous to the tread portion ot the tire', one oi the wing portions having thereon an extension overhanging the other wing portion, and means for applying pressure to said member to flex said wing portions outwardly.

21. An expansible core for tires comprising an arcuate member longitudinally bifurcated in its convex i'ace, the biiiurcated portions being inturned and overlapping one upon the other, and means tor applying pressure to outwardly lex the inturned portions.

22. An expansible core for tires comprising an arcuate tubular meniiber substantially conforming to the interior ot a tire, said tubular member being longitudinally split in that portion contiguous to the tread of the tire to form relatively adjustable inturned wings overlapping` one upon the other7 and means for applying pressure to flex said wings outwardly.

ln testimony whereof, I affix my signature hereto.

EDNARD VRIGHT.

being longitudinally splitv 

